make a copy of headerinclude content, then copy the content of your default template on your headerinclude of your theme.
Then you can see what codes have a conflict with your plugin.
Then you can see what codes have a conflict with your plugin.
The only infinite thing is the universe and human stupidity, but the universe is not for sure
Plugins 1.6.x
Plugins 1.8.x
Plugins 1.6.x
Plugins 1.8.x